Breast Cancer in Men

What is breast cancer in men?

Cancer is made of changed cells that grow out of control. The changed (abnormal) cells often grow to form a lump or mass called a tumor. Cancer cells can also grow into (invade) nearby areas. And they can spread to other parts of the body. This is called metastasis.

Breast cancer occurs in both women and men. Both women and men have breast tissue, and those cells can turn into cancer. 

The most common type of breast cancer in men is infiltrating ductal cancer. This is cancer that starts in milk ducts and spreads to nearby tissues.

Other less-common types of breast cancer in men include ductal carcinoma in situ (DCIS), inflammatory breast cancer, and Paget disease of the nipple. A type of breast cancer called lobular carcinoma in situ is very rare in men. This is because men don't have much lobular tissue. Lobular tissue is where breastmilk is made. 

According to the American Cancer Society, breast cancer is very rare in men. Less than 1 in 100 of all breast cancers occurs in men. It's about 100 times more common in women. 

What causes breast cancer in men?

Doctors think that genes may play a role in breast cancer development in men. These include a family history of breast cancer in a first-degree relative and inherited changes (mutations) of the BRCA genes. Genes other than BRCA and hormone changes may also play a role. But each cancer case is different, and the cause of the breast cancer may never be known. Talk with your provider about your own case.

Which men are at risk for breast cancer?

A risk factor is anything that may increase your chance of having a disease. Risk factors for a certain type of cancer might include smoking, diet, family history, or many other things. The exact cause of someone’s cancer may not be known. But risk factors can make it more likely for a person to have cancer. 

Things you should know about risk factors for cancer: 

  • Risk factors can increase a person's risk, but they do not necessarily cause the disease.

  • Some people with one or more risk factors never develop cancer. Other people can develop cancer and have no risk factors.

  • Some risk factors are very well known. But there is ongoing research about risk factors for many types of cancer.

Some risk factors, such as family history, may not be in your control. But others may be things you can change. Knowing the risk factors can help you make choices that might lower your risk. For example, if an unhealthy diet is a risk factor, you may choose to eat healthy foods. If extra weight is a risk factor, your healthcare provider may check your weight or help you lose weight.

Other risk factors for breast cancer in men include:

  • Being age 60 or older

  • Radiation exposure, such as from radiation used to treat another cancer in the chest area

  • Estrogen treatment, sometimes used for prostate cancer.

  • Diseases linked to high estrogen levels and low levels of male hormones (hyperestrogenism), such as cirrhosis or Klinefelter syndrome

  • Heavy use of alcohol

  • Obesity

  • Female or male first-degree relatives with breast cancer

  • A breast cancer 2 (BRCA2) gene mutation in the family

What are the symptoms of breast cancer in men?

The most common symptoms of breast cancer in men include: 

  • Breast lump or swelling

  • Nipple that turns inward (inversion)

  • Fluid leaking from the nipple (discharge), that may be bloody

  • Skin or nipple changes such as dimpling, puckering, redness, or scaling

Many of these symptoms may be caused by other health problems. It’s important to see a healthcare provider if you have these symptoms. Only a healthcare provider can tell if you have cancer.

How is breast cancer in men diagnosed?

Your healthcare provider will ask about your health history and do a physical exam. Your provider will also do a clinical breast exam. This means carefully feeling the breasts and under the arms for lumps or anything else that seems unusual. You will also need tests. These may include:

  • Ultrasound. This test uses sound waves to take pictures of internal organs or tissues.

  • MRI. This test takes detailed pictures of areas inside the body.

  • Blood chemistry studies. Blood samples are used to measure the amounts of certain substances released into the blood by organs and tissues in the body. An unusual amount of a substance can be a sign of disease.

  • Biopsy. The healthcare provider removes a sample of cells or tissue so they can be looked at under a microscope. These are the types of biopsies:

    • Fine needle aspiration. The provider uses a thin needle to remove tissue or fluid.

    • Core biopsy. The provider uses a wide needle to remove tissue.

    • Excisional biopsy. The provider removes an entire lump of tissue.

If breast cancer is diagnosed, you will likely have other tests. These help your healthcare providers learn more about your cancer. They can help show if the cancer has grown into nearby areas or spread to other parts of your body. The test results help your healthcare providers decide the best ways to treat the cancer. 

How is breast cancer in men staged? 

The stage of a cancer is tells your doctor how much and how far it has spread in your body. The stage of a cancer is one of the most important things to know when deciding how to treat the cancer.

The staging system for male breast cancer is the same as the staging system for female breast cancer. This includes the size of the cancer and whether or not lymph nodes have cancer cells. The stage is based on a 0 to IV scale with 0 meaning the cancer is small and only in the place where it started. Stage IV means the cancer has spread to other parts of the body. Staging affects the choice and outcome of treatment

Your healthcare provider will talk with you about what your cancer stage means for your treatment. Ask any questions or talk about your concerns.

How is breast cancer in men treated? 

The main treatment for male breast cancer is surgery. The most common surgery is a modified radical mastectomy. This means removing the breast, many of the lymph nodes under the arm, the lining over the chest muscles, and sometimes part of the chest wall muscles. 

Other treatments that may be used after surgery include the below.

Radiation therapy

Radiation therapy sends high levels of radiation directly to the cancer cells. Radiation after surgery can kill cancer cells that may not be seen during surgery. Radiation may also be done before surgery to shrink the tumor. It may be done along with chemotherapy. Or it may be used as a palliative treatment. This is a therapy that relieves symptoms, such as pain, but doesn’t treat the disease. Radiation therapy is usually external beam radiation. The machine is controlled by a radiation therapist. Since radiation is used to kill cancer cells and to shrink tumors, special shields may be used to protect the tissue around the treatment area. The treatments are painless and usually last a few minutes.


Chemotherapy is the use of anticancer medicines to kill cancer cells. In most cases, chemotherapy works by interfering with the cancer cell’s ability to grow or reproduce. Different groups of medicines work in different ways to fight cancer cells. The cancer doctor (oncologist) will recommend a treatment plan for each person.

Hormone therapy

In some cases, hormones can kill cancer cells, slow the growth of cancer cells, or stop cancer cells from growing. Hormone therapy as a cancer treatment uses medicines to interfere with the activity of hormones or to stop the production of hormones. Before you begin hormone therapy, your doctor will do a hormone receptor test. This lab test is done on a small piece of the cancer tissue to see if estrogen and progesterone receptors are present. A hormone receptor test can help to predict whether cancer cells are sensitive to hormones. If so, hormone therapy may be given to help keep the hormone away from the cancer cells. 

Key points about breast cancer in men

  • The most common type of breast cancer in men is infiltrating ductal cancer. This is cancer that starts in milk ducts and spreads to nearby tissues.

  • Common symptoms of breast cancer in men is a breast lump or swelling, or a nipple that turns inward (inversion).

  • The main treatment for male breast cancer is surgery. The most common surgery is a modified radical mastectomy.

Next steps

Tips to help you get the most from a visit to your healthcare provider:

  • Know the reason for your visit and what you want to happen.

  • Before your visit, write down questions you want answered.

  • Bring someone with you to help you ask questions and remember what your provider tells you.

  • At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you.

  • Know why a new medicine or treatment is prescribed, and how it will help you. Also know what the side effects are.

  • Ask if your condition can be treated in other ways.

  • Know why a test or procedure is recommended and what the results could mean.

  • Know what to expect if you do not take the medicine or have the test or procedure.

  • If you have a follow-up appointment, write down the date, time, and purpose for that visit.

  • Know how you can contact your provider if you have questions.

Online Medical Reviewer: Marianne Fraser, RN
Online Medical Reviewer: Stump-Sutliff, Kim, RN, MSN, AOCNS
Online Medical Reviewer: Todd Gersten, MD
Date Last Reviewed: 11/13/2018
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